2b0a750caf
If the initial fill blit or copy blit of an object fails, the old content of the data might be exposed and read as soon as either CPU- or GPU PTEs are set up to point at the pages. Intercept the blit fence with an async callback that checks the blit fence for errors and if there are errors performs an async cpu blit instead. If there is a failure to allocate the async dma_fence_work, allocate it on the stack and sync wait for the blit to complete. Add selftests that simulate gpu blit failures and failure to allocate the async dma_fence_work. A previous version of this pach used dma_fence_work, now that's opencoded which adds more code but might lower the latency somewhat in the common non-error case. v3: - Style fixes (Matthew Auld) v4: - Use "#if IS_ENABLED()" instead of #ifdef (Matthew Auld) v5: - Fix an issue where we, if the dependency was already signaled, might end up waiting for a memcpy fence that would never signal. v6: - Add a missing i915_ttm_memcpy_release() (Matthew Auld) Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com> Reviewed-by: Matthew Auld <matthew.auld@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20211104110718.688420-3-thomas.hellstrom@linux.intel.com
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.